"Javascript检查小数是否为负"

Question

How would i check if a decimal is negative? Because the if statement automatically turns it into a number...

Example:

var x = -0.24324; 

how would i parse it so it tells me x is negative/positive?

Thanks

Edit: Maybe i phrased it badly, the variable changes so something it will be positive like 0.00000001 , sometimes -0.0003423423 , sometimes 0.0000000234

If i put it in a if statement everything is automatically turned into 0 right? And i can't use a parseFloat in the if statement?

Answer 1

Just check if x<\/code> less than zero since it's a number:

if (x < 0) {
  // it's negative
}

Answer 2

1. You can use isNaN()<\/code> function to check whether it is valid number or not.<\/li>

Answer 3

const num = -8;

// Old Way

num === 0 ? num : (num > 0 ? 1 : -1); // -1

// ✅ ES6 Way

Math.sign(num); // -1